Question:
I recently had a problem with my printer. I received copies of the 3602s initially and then received the original receipt a week later. Here's the problem: one 3602 showed 4,594 total pieces and I was charged $2,170.47 from my permit account. The sheet attached to the 3602, the "USPS Postage Statement Wizard", shows the same quantity but a postage due amount of $1,501.77. I was requested to submit $1,501.77 in postage for this mailing. That's a $668.70 difference.

When I asked my printer to find out what happened, they told me the weight was incorrect. Well, of 29 mailings, 27 were incorrect. Some were over, others under, with a difference of ($2,144.72) to $668.70. What do I do about this? Is this my printer or the USPS?

Answer:
This particular problem is common with overweight pieces. The scale used by a mailer when evaluating a piece for presort specifications is a different piece of equipment than the scale that the USPS uses when they weigh a sample of the actual mailing. Usually, there is only a slight difference in weight, which would only amount to several dollars overall.

In this case, it may be that your mailer is using weights supplied by presort specifications, then using the postal form created by the presort program itself. If your mailer takes an actual mail piece and weighs it at the time of mailing, they should come up with an actual weight that is very close to what the USPS will get. If the USPS makes a weight change on the 3602 mailing acceptance form, they will typically note the change in the signature area of the 3602 form. Basically, this tells you that your mailer's weight information doesn't actually match the final information derived by the USPS from weighing the actual piece. A conversation with your mailer regarding how they figure their weight estimates is probably a good idea.